The Pure Girl
by Argella
Summary: Would any "affluent child" use godlike power if it fell into her hands? AU oneshot focusing on Sayu.


**A/N: In Volume 3 of the manga, L points out that according to Light's description of what Kira is probably like, the number one suspect would be Sayu Yagami. Soichiro says that Sayu would probably be the type to "kill someone she didn't like, and then cry her head off about it." The title of this story is from the How To Read 13 description of Sayu: "The pure girl whose brother is Kira."**

**_Disclaimer: The plot and characters of Death Note were created by Tsugumi Ohba and Takeshi Obata._**

* * *

**The Pure Girl**

* * *

The schoolroom was full of muffled whispers and giggles, as it usually was during the math period when everyone was the most bored. Sayu cast a quick, slightly guilty glance toward the front of the room, but turned back to her friend a moment later with a smile. Mizumi had been telling her excitedly about the upcoming Hideki Ryuuga concert at the Yoyogi National Stadium. Sayu couldn't help listening, even though she was supposed to be paying attention to the lesson about the Quadratic Formula.

"Yagami," the teacher called, making Sayu jump to attention. "Will you please come up to the board and solve this equation?"

Her heart sank as she stood up and smoothed her skirt nervously. "Yes, sir." She tried to make sense of the formula that was scrawled on the chalkboard, but felt her eyes start to cross at the multitude of symbols. Why did algebra have to be so hard?

"Come on, Yagami, start with identifying the coefficients," the teacher prompted her gently. Sayu nodded, remembering after a few seconds what a coefficient was. She studiously copied the formula from the other side of the board, biting her lip in embarrassment when she forgot the negative sign and the teacher had to correct her. When Mizumi was called up to finish the problem, Sayu hurried back to her desk in relief.

Now that Mizumi's seat was briefly empty, Sayu had an uninhibited view of the window that overlooked the school grounds. It was a sunny day in late November, but the weather was just starting to get chilly. A light breeze ruffled the leaves on the tree across from Sayu's classroom. Sayu gazed dreamily at the sky, wondering if her mother would allow her to attend the Hideki Ryuuga concert in two weeks. Her nose wrinkled at the thought that she would probably have to pull up her grades in algebra before Sachiko would even consider it.

She sighed and was about to turn back to the blackboard when an odd movement caught her eye—a flat black object tumbling through the air. As it fell past Sayu's line of sight, the wind turned it over, showing a brief flash of white fluttering pages. A notebook? How odd. Had someone thrown it from an upper story?

Her puzzlement was forgotten as Mizumi sat down again, shooting Sayu a grin. Sayu looked back at the two solutions circled on the board and whispered, "How do you remember how to do that? I always forget which coefficient is which."

Mizumi shrugged. "It's not that hard. Why don't you ask your brother to help you? He's pretty smart."

Sayu huffed out a quiet, indignant breath. "I'm smart, too!"

"Yeah, yeah," her friend replied, rolling her eyes good-naturedly. The bell rang and the students busied themselves with packing up their notes and pencils and textbooks. Sayu wanted to hurry home today so that she could ask Light to help her with her homework right when he came home from school.

As she raced down the stairs and out the door into the sunshine, she remembered the strange sight of the falling notebook, and tried to remember where it would have hit the ground. She squinted at the edge of the lawn—there it was. Perhaps she should turn it in at the school office, in case someone had lost it.

Sayu bent down to pick up the thin black book, which had fallen face-down in the grass. The cover had spiky characters on it that Sayu could barely read. Was it English?

"D-E-A-T-H-N-O-T-E," she quietly sounded out, trying to remember her English vocabulary. She flipped curiously through the book—the pages were all blank, but there was more English text written on the inside cover. She knew it would be a headache to try to translate all of it.

Well, if the notebook was empty, probably no one would miss it—she might as well keep it. She tucked it into her backpack and set off for home, wondering if Light would be able to tell her what all the English words said.

* * *

"Hey, Mom," Sayu called as she kicked off her shoes and peeked into the kitchen. "Is Light home yet?"

"No, remember, he has his test prep class after school today," Sachiko said from behind the counter, where she was chopping carrots.

Oh, right. Sayu could never remember all the details of her brother's schedule. "Tell me when he comes home, okay? I need some help with my homework."

"All right. But he probably won't be home until dinner," Sachiko told her daughter, glancing up with a smile. "Do you want some fruit?" she asked, gesturing with her knife to the glass bowl at the end of the counter. "The apples are delicious; I just had one."

"No thanks, Mom. Maybe later." Sayu skipped up the stairs to her room, deciding that she wouldn't attempt the incomprehensible math homework until Light came home. She flopped down on her bed and took out the mysterious notebook from her backpack.

The cover felt strange in her hands, a bit slippery and cold. It didn't feel like it was made from cardboard, plastic, or cloth binding. It was probably expensive. At least the inside pages seemed to be made of ordinary paper. She flipped through the blank pages absently, wondering why someone would want to throw such a nice notebook out of a window.

Fueled by a sudden curiosity, Sayu jumped up from the bed and took her English dictionary from the bookshelf. Translating the text on the inside cover would be a fun puzzle to solve before starting her non-algebra homework. Maybe the text would say where the notebook came from, or to whom it belonged.

Sayu was relatively quick at finding words in dictionaries, but she thought she must have translated the first sentence incorrectly. _The human whose name is written in this note shall die..._ A notebook that caused people to die sounded pretty stupid. But after spending an hour looking up meanings and juggling them around in her head, it seemed that the words on the cover really were instructions for operating a... notebook of death.

"Hmph," Sayu muttered, closing the dictionary and placing it on her bedside table. Why would anyone want to pretend something so morbid—that you could kill someone simply by writing down a name? It sounded like a sick joke to her. Maybe that's why the notebook had been tossed out of a window—either because the previous owner had been disgusted by the premise, or because he'd wanted to play a joke on the next person to pick it up. She was glad that she hadn't asked Light to translate the text for her—he probably would have thought that his dumb little sister had started becoming obsessed with supernatural stuff.

She stuffed the notebook into one of her desk drawers, pushed all thoughts of it out of her mind, and sat down to begin her homework.

* * *

At dinner, Sayu happily sipped at her mother's excellent miso soup, quietly listening to the conversation. Her dad was talking to Light about some case he had just solved. "So this guy killed five kids? How awful," Light remarked, frowning and setting down his chopsticks. "I hope he gets convicted."

"It's likely he will be," Soichiro said, pinching the bridge of his nose and looking tired. "It isn't often that a trial like this ends with a not-guilty verdict, especially with any amount of evidence. Our justice system does not look kindly upon accused murderers."

"Is the trial going to be on the news?" Light asked. "It seems like a pretty high-profile case. Is the press going to interview you?"

"Wow, does that mean you'd be on TV, Dad?" Sayu piped up after swallowing a mouthful of soup. "That'd be cool!"

Soichiro smiled sadly at his daughter. "Maybe. But it wouldn't be like your Hideki Ryuuga appearing on television." Sayu suppressed a smile—it was amusing to hear her stern, middle-aged father mention the name of a teenage pop idol. "This is very sad business—five children are dead, and the one who killed them will probably be executed." Her father shook his head. "I'm glad we caught him, but it's certainly not something I would celebrate. You shouldn't even watch things like that on the news, Sayu."

Light was still scowling faintly. "What's this scumbag's name? I don't think I heard about this on the evening report." Of course Soichiro was not allowed to discuss suspects by name until after the case had been solved, but Light always kept tabs on his father's cases once they were public knowledge. He watched the news more often than most grown-ups Sayu knew.

"Kuro Otoharada," Soichiro replied, picking up a piece of fish. "The case will probably be mentioned on the night report. You're right, it's rather high-profile."

"That's enough talk of murderers and trials," reprimanded Sachiko. "Light, how did you do on the exams? The results were handed back today, right?"

Light smiled and rattled off his exam scores. Sayu went back to drinking her soup, feeling proud of her brother. He'd probably go on to do cool, important things, just like their dad. No one would have guessed that a daughter from such an intelligent family was barely passing algebra.

* * *

Sayu was still awake at 23:00, even though she was ready for bed. Light had said he wanted to turn in early after helping her with her algebra problem set. All four of them had watched the news, and Soichiro and Sachiko had retired soon afterward. The Yagami family didn't tend to stay up late on Friday nights.

Thoughts of murder trials and executions had been at the back of Sayu's mind ever since dinner, and now she couldn't fall asleep. The shapes of the eerie silvery letters on the cover of the notebook seemed to be imprinted on the inside of her eyelids, along with the name and picture of the murderer from the nighttime news report. She frowned in the direction of her desk.

Sighing, she flicked on her lamp, got out of bed and retrieved the notebook. She sat down on the mattress again with her back to the wall, and held the book open in her lap, staring at the spiky words written on the inside cover.

_The human whose name is written in this note shall die._

Sayu shuddered and closed her eyes. Unbidden, her mind conjured an image of the five murdered children, their blank eyes staring out of death-swollen faces, lying in dark pools of blood.

Murder repaid with slaughter... how horrible. They would lead the killer to a plain white chamber with a noose hanging from the ceiling, and blindfold him. He would stand in the darkness, waiting for the last seconds of his life to tick by, and then—_crack_—

Her eyes snapped open and she felt her pulse quicken. _Stop it!_ Sayu shook herself and wrapped her arms around her knees, letting the notebook slip from her lap. _The murderer has nothing to do with you. People commit awful crimes and get executed all the time..._

She stared at her bookshelf. The shadows from her bedside lamp were long and menacing, reminding her of knives. Sayu groaned and rubbed her eyes. _You're acting like such a baby. When was the last time you got this freaked out over one of Dad's cases?_

It had been many years since Sayu had allowed herself to picture any of the atrocities that her father had to work with on a daily basis. Soichiro used to sweep her up in his arms and hold her, telling her that he would keep her safe. It was his job to keep everybody safe. He caught murderers and robbers and thieves and turned them over to the law so that they would pay for their crimes and never harm anyone again.

So many criminals. How many had her father indirectly sent to their deaths? How many more were out there—how many would never be caught?

_This is ridiculous._ Sayu leaned toward her nightstand and opened the drawer, searching around for a pen. Her mother had taught her the trick of writing down her worries so that they would bother her less. A fear always had less power when trapped on paper. She would be able to see how silly her thoughts were once she wrote them down.

Her fingers found an old ballpoint. She yanked the cap off the pen and shook it out a bit to make sure the ink would flow. Then she set the pen to the first page, trying to keep her hand from trembling.

_Kuro Otoharada is an evil man. He stabbed five children to death. He deserves to die,_ she wrote in neat script, remembering the correct kanji for the killer's name from the news report. _He can't hurt me. Dad caught him and he will be hanged._

Sayu read over the sentences several times, even whispering them aloud, until the words began to lose meaning. _There, that should do it._ Feeling considerably calmer, she closed the notebook and put it and the pen into her nightstand drawer. She forced herself to think about nothing but Hideki Ryuuga until she drifted off to sleep.

* * *

She was woken at 8:30 the next morning when the phone rang downstairs. She blinked and yawned, hearing her father's muted voice from the floor below. He sounded agitated. Swinging her legs out of bed, she decided to forego getting dressed or combing her hair until after breakfast.

As she neared the upper landing of the stairs, she heard her mother's voice. "Soichiro? What was that about? Why was the office calling you on a Saturday?"

There was a pause before her father answered. "Kuro Otoharada is dead. He was found in his cell at around a quarter to midnight last night. It looks like he suffered a heart attack. They were just calling to let me know..."

Sachiko harrumphed. "Well, it doesn't seem that important to me. No reason for them to be calling you on your off day, just to disturb you with news that doesn't really concern you."

"I suppose you're right," Soichiro conceded. "But the circumstances of his death were rather odd. He had no prior history of cardiovascular disease. I wonder if he was ill and no one knew?" He sighed. "Well, they'll perform an autopsy to confirm. But Sachiko, it's so strange—it almost seems as though this man were struck down from on high." He let out a short laugh.

"Well, that saves the legal system the trouble," Sachiko said lightly. "Come on, dear, you need some breakfast."

Sayu remained frozen on the landing for several long minutes, while sounds and smells of her mother preparing breakfast drifted up from the kitchen. Then she slowly backed up the stairs and walked down the hallway to her room, closing the door silently after she entered.

She sank down on her bed, shaking. _Did I kill him? I couldn't have killed him... it's impossible._

But her father had said it. The murderer had been struck down from on high. His death wasn't natural. And this notebook had come from the sky...

Sayu wrapped her bedcovers around her shivering body, hiding in them like a cocooned insect.

_I killed him. I wrote his name and killed him._

When her mother called her down for breakfast, she buried herself further into her blankets, her wide eyes leaking tears. She did not answer.

* * *

"Sayu? Are you still sleeping?" Light's voice sounded from behind her door a few hours later. "Mom said to check on you. Do you want lunch?"

She didn't emerge from the bedcovers. She heard herself hoarsely reply, "I'm not feeling well. Go away." She hadn't stopped shuddering.

"Oh... Do you want me to bring you some food?"

"No," she said forcefully, her voice nearly cracking. "Please go away." She heard silence beyond the door, then the sound of receding footsteps.

Six hours after that, she didn't reply when her mother asked if she would come eat dinner. She wondered what it was like to be dead.

* * *

She had to get rid of the notebook. Destroy it. It was an evil object. It had made her a murderer. Just like the man who had knifed five children and left them bleeding in the street...

_Be strong, Sayu. You have to do it. So that you can never hurt anyone again. Get rid of it._

The rest of the household was asleep now. There was no one to ask her what she was doing with a weird-looking black notebook with English writing on it. She had to do it now. How would she destroy it? Could she tear or cut it up? Bury it? Burn it?

She had to make sure no one could ever use it again, even by accident. She had to burn it so completely that whatever demonic power possessed it would be gone forever. Biting her lip and ignoring her churning stomach, she carefully pushed back her blankets and opened the drawer where the notebook was.

A thin sheen of sweat covered her body, making her shivering start again; she put on a dressing gown and her warmest slippers. Then she gingerly picked up the notebook between her thumb and forefinger, exited her room, and tiptoed down the stairs, staying close to the wall to avoid making the steps creak.

She found a book of matches in the kitchen and pushed open the back door of the house. There was no wind tonight—good. Nothing to disturb the fire she was going to light. The best place would be in the middle of the garden, on a wide patch of gravel away from anything else that could burn.

When she struck the match and set it to the notebook, the flame caught and turned bright blue. Sayu turned and ran back into the house as soon as she was sure the fire would completely consume the book. She didn't care about the small danger of leaving an open flame unattended—the otherworldly blue fire was too terrifying to watch. She would go out again tomorrow morning to make sure that all that remained was a pile of ashes.

As soon as she entered the kitchen, closed and locked the door again, she stood for a while as though waking from a bout of sleepwalking. She blinked and tried to remember what she was doing in the kitchen in the middle of the night.

Her stomach grumbled. Of course, she had slept all day because she had been sick, and now she had come down to get food. She found a small bag of potato chips in a kitchen cabinet, made sure they weren't that disgusting flavor that Light seemed to enjoy, and took them back upstairs to her room. Potato chips probably weren't the best thing to eat on an unsettled stomach, but she was too hungry to care. After she finished the entire bag, she fell into bed and slept deeply until the next morning.

* * *

Her mother knocked on her door at 9:30. "Are you feeling all right, Sayu? May I come in?"

Sayu rolled over and stretched out her arms. "Sure, Mom," she croaked. Why did her mouth taste so gross? Oh, right. The late-night potato chips.

The door opened and Sachiko's face poked in. "I heard some noise last night. Did you go downstairs?"

"Yeah, I was hungry." Sayu sat up and rubbed her eyes.

Her mother smiled. "You must have had a stomach bug. Do you feel better now? Are you ready for breakfast?" She sat down on Sayu's bed and put an arm around her daughter's shoulders. "I was worried you wouldn't sleep well last night, since you napped all day. But you seem fine."

Sayu nodded sleepily, leaning into her mother's hug. "I'm okay. I'll come downstairs now." She allowed her mother to lead her out of her room and down to the kitchen, where Sachiko fussed over her and made her tea. Light and Soichiro said they were glad she was feeling better, since it was a school day tomorrow.

The Yagami family didn't mention or discuss the mysterious death of Kuro Otoharada; the press would soon forget about it. The small pile of cinders in the back garden had been blown away by the cold breeze in the early hours of the morning.

A world away, a dark skeletal form peered down and shrugged his wide shoulders. He decided that, all in all, the events that had played out hadn't been very interesting. Perhaps he could try again some other time.


End file.
